The Congressional Budget Office estimates that 23 million Americans would migrate from employer-based health care plans or other plans to a government public health care plan if one were offered. A study by health consulting firm the Lewin Group found that if a government-run plan paid at the same rate as Medicare, 70 percent of consumers currently with private insurers would jump ship for the public program.

"A government plan, no matter what you call it, will increase costs. It will reduce choices and essentially it will not allow you to keep what you have, and that is the essence of what the health care system in this country is about," said Rep. Eric Cantor, R-Va., echoing the sentiment of his fellow Republican congress members. "We ought to allow for more competition so that people can have choice."

A CBS/New York Times poll found that 72 percent of Americans support a public option, and 50 percent think government would do a better job providing medical coverage than private insurers do. Only 30 percent of those polled said they did not think providing health insurance for all Americans was the government's responsibility.

According to recent estimates, 59 percent of Americans get health insurance through an employer. But 45.7 million people in the United States, including 8 million children, have no health insurance at all.

Who Pays for It?

Cost has also become a hot button issue -- namely, how will any new plan be funded?

Former majority leaders of the Senate, Tom Daschle, Howard Baker and Bob Dole, who have offered their own bipartisan solution, say that at least half of the costs to pay for health care reform would have to come from new revenue and taxes. White House officials say that's not true.

"I think people are thinking that this is brand new money that's being printed," said President Obama's domestic policy adviser Melody Barnes. "There's already $2 trillion worth of health care that's being spent already. This is redirecting that money so it's more efficiently and effectively used and so people are getting better quality health care."

"What the Republican plan will do is, it will look more toward the individual and will say, if you have a plan, your insurer and you are going to determine the length of that coverage," Cantor said on "GMA." "But also if somehow you lose your job and that's how you get your coverage, we're going to make sure that you have the flexibility under that plan to take that coverage with you."

Health Care Debate on Preventive Measures

Officials say one way to cut health care industry costs in the long run is to put procedures in the plan that would reduce unnecessary tests that doctors conduct.

"Right now, we pay doctors based on how many times they touch a patient, how many tests are given, how many procedures are run. Not how well the patient is at the end of the day," Sebelius said.

Officials cite reports such as those in a recent Dartmouth University study that found that up to 30 percent of medical spending -- $700 billion a year -- does nothing to improve health.

But who will decide what tests are necessary?

"Clinicians will make those decisions," said Nancy-Ann DeParle, director of White House Office of Health Reform. "What we're trying to do and the president is trying to get is a system where we can have lower costs for all families and businesses."

"No one's going to tell your doctor that he or she can't do a procedure, but there will be a set of protocols that we know at the end of the day actually produce a better result for you and are less intrusive," Sebelius said. "Do what works best for me, and that's really what we're talking about. Not cheaper medicine, better medicine each and every time."

Doctors say they need more protection against medical malpractice lawsuits if they are to cut the number of tests they prescribe.

But in a speech to the American Medical Association last week, Obama was noncommittal on that end, saying only that his administration wants to work with doctors to cut back "excessive defensive medicine.

"I recognize that it will be hard to make some of these changes if doctors feel like they're constantly looking over their shoulders for fear of lawsuits. ... I understand some doctors may feel the need to order more tests and treatments to avoid being legally vulnerable. That's a real issue," Obama said. "I'm not advocating caps on malpractice awards, which I personally believe can be unfair to people who've been wrongfully harmed."

The Healthy Life

Another component of the White House health reform plan, officials say, is to encourage Americans to live healthier lives. Health and Human Services estimates that 54 percent of all U.S. health care costs are due to three mostly preventable conditions: heart disease, diabetes and obesity. Eighty percent of heart disease, obesity and cardiovascular disease is preventable.

"Some of that is about personal responsibility but it's also making sure that there are incentives for businesses. We're working with CEOs recently who came in and said, 'We're working with our staff to make sure that we're reducing obesity rates and working on tobacco cessation,'" Barnes said.

Doctors say the government needs to create a grassroots effort simply to get Americans to walk a little bit every day.

"If I could pick one single thing for all Americans to do, it would be walking, because I know it would cut into the rates of diabetes, hypertension, obesity and cardiovascular disease," said Dr. Mehmet Oz. "Just 30 minutes a day is the magic number. It would be a national policy that's easy to follow and would have a dramatic impact."